Chaetocnema (Udorpes) singala Maulik, 1926

Ruan, Yongying, Yang, Xingke, Konstantinov, Alexander S., Prathapan, Kaniyarikkal D. & Zhang, Mengna, 2019, Revision of the Oriental Chaetocnema species (Coleoptera, Chrysomelidae, Galerucinae, Alticini), Zootaxa 4699 (1), pp. 1-206 : 190-191

81. Chaetocnema (Udorpes) singala Maulik, 1926

( Fig. 110 )

Chaetocnema singala Maulik, 1926: 204 , 212. TL: Ceylon. TD: BMNH. Lectotype designated here.

Distribution: Sri Lanka ( Ceylon).

Host plants: Unknown.

Description: Body length: 1.90–2.00 mm. Body width: 1.05–1.10 mm. Ratio of elytron length (along suture) to width (maximum): 2.20–2.25. Ratio of pronotum width (at base) to length: 1.61–1.64. Ratio of length of elytron to length of pronotum (along middle): 2.50–2.55. Ratio of width of elytra at base (in middle of humeral calli) to width of pronotum at base: 1.05–1.10.

Elytra red brown, with slight bronzy luster; pronotum and head bronzy. Antennomeres completely yellow brown, with distal ones slightly darker. Tibiae and tarsi yellow brown. Pro- and mesofemur red brown. Metafemur deep red brown, with slight metallic luster.

Head hypognathous. Frontal ridge wide and flat. Frons covered with closely placed punctures. Ratio of width of frontal ridge to width of antennal socket: 2.20–2.30. Frontolateral sulcus absent. Suprafrontal sulcus moderately deep, with a pit in middle. Frons and vertex evenly covered with large and closely placed punctures. Vertex situated on same level as orbit.

Base of pronotum without short longitudinal impressions. Pronotal base evenly convex. Deep row of large punctures at base of pronotum absent. Area adjacent to mid-basal margin of pronotum covered with punctures. Anterolateral prothoracic callosity weakly developed, almost invisible in dorsal view. Lateral margins of pronotum nearly evenly convex, with maximum width near middle. Posterolateral prothoracic callosity poorly developed. Diameter of pronotal punctures 1.5–3 times smaller than distance between them.

Humeral callus well-developed. Elytra with convex lateral sides. Scutellar row of elytral punctures almost single. Second to eleventh rows of elytral punctures regular.

Excavation on metatibia moderately developed. Large lateral denticle on metatibia obtuse. Metatibial serration proximal to large lateral denticle absent.

Types: Lectotype: 1 female ( BMNH), 1) Type; 2) Colombo, Ceylon, May, H P Green, 1916–157; 3) Chaetocnema singala Mlk., Det. S. Maulik , Type, 1925.; 4 ) Lectotype Chaetocnema singala Maulik, 1926 Des. Ruan et al., 2016 .

Remarks: C. singala is extremely close to C. bretinghami , except for the slight difference in body size and elytral punctation (body size slightly smaller in C. singala ; peri-scutellar punctures single in C. singala , while geminate in C. bretinghami ). It is uncertain to us whether C. singala and C. bretinghami are conspecific. As the types of C. singala comprises only one female specimen, it is hard to reach an unequivocal decision on the status of these two species.

Figures

FIGURE 110. Chaetocnema singala. A Lectotype, habitus. B Head of Lectotype, frontal view. C Pronotum of Lectotype.